1. Field of the Invention
The invention refers to a device for determining the condition of railway switches or railway crossings comprising sensors for monitoring the end position of tongue rails, in particular for the diagnosis of the wear and for laying down maintainance intervals.
2. Description of the Prior Art
Monitoring devices for the spatial position of swivelable rails can be derived, for example, from AT-PS 358 625. The known monitoring devices having been used in connection with railway switches and railway crossings were restricted to provide repeating signals for the end positions of swivelable rails, so that the track can be given free after the correct end position of the swivelable rails has been acknowledged. Such devices were primarily used in remote control devices and, respectively, in interlocking posts or local control devices, and from EP-A-153 900 it has already become known to incorporate into the control of the end position also the surveyance of the switch drive means. Premature wear of switch parts can only insufficiently be recognized by such devices and it is in particular not possible to establish with the known devices a diagnosis system which is capable of determining data that is important for the operation of the switch at a distance from the switch drive means itself and, respectively, from the ends of the tongue rails and which is in particular capable of recognizing premature wear.